I want to dual boot windows 7 x64 and ubuntu 13.04 x64, but when I installed it, it doesn't boot. Only windows was booting. I installed ubuntu with " / " 50GB and a "swap" partition 4GB. Could it be that it doesn't work because I'm on bios mode, and that my disk is MBR, not GPT. My laptop doesn't have an option to change boot mode to UEFI so as much as possible, I'd stick to MBR :( Acer Aspire 4755G Intel i5-2450M 2.5Ghz-3.1Ghz Nvidia GeForce GT540M 2GB 4GB RAM DDR3